1. Field of the Invention
The present invention relates to a multi-piece solid golf ball of outstanding rebound, spin, feel and distance which has an elastic solid core enclosed within a plurality of resin layers of differing physical characteristics.
2. Prior Art
Golf balls in recent years have seen an overwhelming shift in preference take place from thread-wound constructions to solid constructions on account of the excellent distance achieved by the latter. At first, a solid construction typically referred to a two-piece solid golf ball in which the center, which represents most of the ball, is composed of a solid rubber core of excellent impact resilience and is enclosed within a hard resin cover such as one made of ionomer resin for protection from external damage.
However, although such a construction provides an excellent distance, the deformation at the time of impact is smaller than that of thread-wound balls, resulting in a hard and unpleasant feel. Also, the small deformation means that the surface area of contact with the clubface is small, giving the ball a poor spin receptivity and poor controllability on shots taken with an iron. Various attempts have been made to overcome such drawbacks, such as lowering the hardness of the solid core, placing a buffer layer between the core and the cover, and using a relatively soft polyurethane as the cover material.
Such modifications have made it possible to largely achieve the desired improvements in feel and spin rate. Yet, these improvements have been accompanied by a number of new problems, such as a decline in carry—originally a desirable attribute of solid ball constructions, due to a smaller rebound. Another new problem has been the ball's excessive receptivity to spin when hit for distance with a wood club, particularly a driver, resulting instead in a somewhat skying shot that fails to achieve the desired distance. Little progress has been made in overcoming these problems.